xref: /kvmtool/include/kvm/disk-image.h (revision c1ed214e170343d8ca46770a36ea629bfa2d99ba)
1 #ifndef KVM__DISK_IMAGE_H
2 #define KVM__DISK_IMAGE_H
3 
4 #include "kvm/read-write.h"
5 #include "kvm/util.h"
6 
7 #include <linux/types.h>
8 #include <linux/fs.h>	/* for BLKGETSIZE64 */
9 #include <sys/ioctl.h>
10 #include <sys/types.h>
11 #include <sys/mman.h>
12 #include <sys/stat.h>
13 #include <stdbool.h>
14 #include <sys/uio.h>
15 #include <stdbool.h>
16 #include <stddef.h>
17 #include <stdlib.h>
18 #include <unistd.h>
19 #include <fcntl.h>
20 
21 #define SECTOR_SHIFT		9
22 #define SECTOR_SIZE		(1UL << SECTOR_SHIFT)
23 
24 #define DISK_IMAGE_MMAP		0
25 #define DISK_IMAGE_NOMMAP	1
26 #define MAX_DISK_IMAGES         4
27 
28 struct disk_image;
29 
30 struct disk_image_operations {
31 	/*
32 	 * The following two are used for reading or writing with a single buffer.
33 	 * The implentation can use readv/writev or memcpy.
34 	 */
35 	ssize_t (*read_sector)(struct disk_image *disk, u64 sector, void *dst, u32 dst_len);
36 	ssize_t (*write_sector)(struct disk_image *disk, u64 sector, void *src, u32 src_len);
37 	/*
38 	 * The following two are used for reading or writing with multiple buffers.
39 	 * The implentation can use readv/writev or memcpy.
40 	 */
41 	ssize_t (*read_sector_iov)(struct disk_image *disk, u64 sector, const struct iovec *iov, int iovcount);
42 	ssize_t (*write_sector_iov)(struct disk_image *disk, u64 sector, const struct iovec *iov, int iovcount);
43 	int (*flush)(struct disk_image *disk);
44 	int (*close)(struct disk_image *disk);
45 };
46 
47 struct disk_image {
48 	int				fd;
49 	u64				size;
50 	struct disk_image_operations	*ops;
51 	void				*priv;
52 };
53 
54 struct disk_image *disk_image__open(const char *filename, bool readonly);
55 struct disk_image **disk_image__open_all(const char **filenames, bool *readonly, int count);
56 struct disk_image *disk_image__new(int fd, u64 size, struct disk_image_operations *ops, int mmap);
57 int disk_image__close(struct disk_image *disk);
58 int disk_image__flush(struct disk_image *disk);
59 ssize_t disk_image__read(struct disk_image *disk, u64 sector, const struct iovec *iov, int iovcount);
60 ssize_t disk_image__write(struct disk_image *disk, u64 sector, const struct iovec *iov, int iovcount);
61 
62 struct disk_image *raw_image__probe(int fd, struct stat *st, bool readonly);
63 struct disk_image *blkdev__probe(const char *filename, struct stat *st);
64 
65 ssize_t raw_image__read_sector_iov(struct disk_image *disk, u64 sector, const struct iovec *iov, int iovcount);
66 ssize_t raw_image__write_sector_iov(struct disk_image *disk, u64 sector, const struct iovec *iov, int iovcount);
67 ssize_t raw_image__read_sector(struct disk_image *disk, u64 sector, void *dst, u32 dst_len);
68 ssize_t raw_image__write_sector(struct disk_image *disk, u64 sector, void *src, u32 src_len);
69 int raw_image__close(struct disk_image *disk);
70 
71 #endif /* KVM__DISK_IMAGE_H */
72